Terrence Reynolds said the pavement “requires some serious oversight ... and a fair amount of ongoing maintenance.”
View full sizeA southerly aerial view of Parsons Village from the Valley CDC's special permit application, filed December 28, 2010.EASTHAMPTON – Opponents of the proposed Parsons Village affordable housing project have taken issue with the stormwater management system the developer is planning to use.
The type of pavement being proposed to be used, known as porous pavement, has a high number of air voids that allow water to pass through several layers of filters and slowly infiltrate into the subsoil. No catch basins are necessary, but Northampton-based Valley Community Development Corp. has agreed to include two at the edge of the property as back-ups.
Joanne Campbell, executive director of Valley CDC, said the pavement is practical, cost-effective and good for the environment. The National Asphalt Pavement Association’s website says “such pavements have been proving their worth since the mid-1970s.”
Parsons Village’s potential neighbors commissioned a report from T. Reynolds Engineering in Whately. It shows a few places where the design needs work, such as substandard erosion control and a missing “blanket” between the filter course and reservoir course.
Owner Terrence R. Reynolds said the pavement “requires some serious oversight ... and a fair amount of ongoing maintenance.”
Amy Heflin said Valley CDC’s promise to perform maintenance once every six months is not nearly good enough. The Metropolitan Area Planning Council, based in Boston, calls for monthly surface cleaning and vacuuming at least three times a year.
Peter Wells of Northampton-based Berkshire Design Group, the project’s civil engineers, said “multiple studies” have shown the CDC’s schedule will be adequate.
Cars would have to be moved in order for the work to be done. Reynolds said that if it were his development, he would avoid using porous pavement for that reason.
“Logistically, it’s kind of a pain in the neck with 24/7 residents on it,” he said.
Many abutters who have spoken out at Planning Board special permit hearings are concerned their basements will flood if the pavement fails, especially since the site has a notoriously high water table that has caused floods many times before. Wells said that won’t happen.
“We anticipate no standing water or ice puddles because the water permeates right away,” he said. “The pavement can clog up to 99 percent and still function.”
There can be no sanding in the winter because it could clog the air voids, according to the U.S. Environmental Protection Agency, which also reports that clogging can increase with age and use.
The MAPC says “it cannot be used in high-traffic areas or where it will be subject to heavy axle loads,” which could make trash removal with dump trucks a problem.
“You get a lot of that sort of traffic in there and it gets crushed ... and loses its porosity,” said Reynolds.
Wells said if any of the pavement is compressed, the water will just find a new place to permeate.
Valley CDC has offered to place $12,000 in an escrow account for eight years and issue annual reports on the maintenance. If the pavement were not properly maintained, the city could use that money to pay for the work.
“We have done good developments,” said Campbell. She said the CDC’s record shows their projects “remain in good condition.”